A conventionally known control device for a stepless transmission (a continuously variable transmission) includes: an input-side element configured to receive power from a power source of a vehicle; an output-side element configured to output the power to the drive wheels of the vehicle; and a transmission element configured to transmit the power from the input-side element to the output-side element (for example, see Patent Literature 1). The control device for the stepless transmission determines the clamping force of the input-side element and the output-side element so that the transmission gear ratio of the stepless transmission is a target transmission gear ratio which is the target value of the stepless transmission.
Such a stepless transmission is required to have no significant slippage between each of the input-side element and the output-side element and the transmission element, to efficiently transmit power from the input-side element to the output-side element. The friction coefficient between each of the input-side element and the output-side element and the transmission element changes depending on the temperature of a lubricant interposed between each of the input-side element and the output-side element and the transmission element. Hence, the control device for the stepless transmission corrects the clamping force of the input-side element and output-side element according to the temperature of the lubricant.